Blasting by on the
Autobahn, you might never notice anything unusual about the 7-Series sedan BMW
rolled out in
Berlin last week. Indeed, even sitting behind
the wheel, you might not sense anything unusual, despite the glowing amber “H”
in the instrument panel.

Not until you stop to fuel up,
that is, at the Total station on the outskirts of the German capital. Hit the
filler release and a motorized door on the right rear pillar whirs open,
revealing a stainless steel contraption definitely not for use with your
everyday gasoline pump. It is, in fact, the most visible piece of the complex,
bi-fuel powertrain that powers the most unique version of the BMW 7-Series to
roll off the automaker’s Munich assembly line.

“We’ve reached an important
milestone on our way to an era of sustainable mobility,” declared Klaus Draeger,
BMW’s board member in charge of research, during the media preview of the
Hydrogen 7, which can run on either petrol or hydrogen.

BMW is by no means the only
automaker looking to the lightweight gas as the clean fuel of the future, but
where most competitors are emphasizing space-tech fuel cells, the Bavarian
manufacturer is taking a decidedly different approach with the Hydrogen 7
sedan.

What starts out as a relatively
conventional 760Li — including the sedan’s 6.0-liter V-12 engine — undergoes
significant modifications before it rolls off the line. That starts with the
cryogenic fuel tank tucked neatly between back seat and trunk. Bucking the
general industry trend towards using compressed hydrogen, BMW engineers chose to
maximize range by using the cryogenic form of the fuel — in liquid form, it must
be supercooled to -253 degrees C, or just barely above absolute
zero.

Sophisticated engine control
software makes the car feel just like a conventional 760Li. Indeed, pressing the
“H” button on the steering wheel to switch between fuels, a passenger might not
even notice. Engine output has been detuned to 260 bhp. But despite its bulk,
the sedan is still reasonably quick, in either mode launching from 0-100 km/h
(0-62 mph) in just 9.5 seconds, with a limited top speed of 230 km/h, or roughly
145 mph.

During a day of driving around
Berlin, we
found it almost impossible to tell what fuel you were using without checking the
instrument panel. There’s only the slightest shudder switching back and forth
between gasoline and hydrogen, far smoother than even the silky smooth BMW
six-speed automatic.

Under hard acceleration, there’s a
slight bit more engine noise when running on hydrogen, more like a BMW diesel,
but a bit more brittle-sounding, due to the way the gaseous fuel detonates.

The Hydrogen 7 only can hold about
six kilograms of the fuel in its cryogenic tank — which swallows up half the
sedan’s trunk space and four inches of rear legroom. That’s enough to get you
just 125 miles — if you’re not too aggressive with the throttle. During our fast
morning drive, we found ourselves getting about a third less mileage than
promised.

After that, you’ll need to switch
to gasoline power or find one of the rare liquid hydrogen pumps, like the one at
a Total station a few minutes outside downtown
Berlin. After hooking up the hefty refueling
apparatus to the thermos-like H2 filler port, it took eight minutes to top off
and get running again. (We hadn’t used enough gasoline to draw a refill for that
tank.)

Cost
killer

All-in-all, we’d have no problems
using the Hydrogen 7 as our daily driver — if we had a ready supply of hydrogen,
of course, and didn’t have to pay for all that added hardware. BMW officials
won’t reveal how much it costs, though Timm Kehler, marketing manager for BMW’s
so-called “Innovations” unit, conceded it’s substantial.

Still, he asserted, “Our customers
are willing to pay for innovations. It’s part of the brand philosophy.”
Actually, most drivers likely will pay little to nothing, as BMW is using the
Hydrogen 7 as a combined research and marketing program.

In all, BMW intends to produce
just 100 Hydrogen 7 sedans, nearly half earmarked for
Berlin, most of the rest for
Los
Angeles. A few more
will go to other parts of Europe, the
U.S. and
Asia.
For markets with no ready sources of liquid hydrogen — which means most of the
world — the automaker is readying a support fleet of mobile H2
tankers.

Despite all the hype about
hydrogen, it’s unclear what the fuel’s future holds. On the positive side, it
burns cleaner than anything else available. Burned in the Hydrogen 7’s V-12, it
turns into little more than water vapor, with minute trace amounts of
smog-forming nitrogen oxides and hydrocarbons from the oil used to lubricate the
engine’s pistons.

Skeptics would contend that
there’s an even cleaner alternative, the hydrogen-powered fuel cell favored by
most other manufacturers. But Hydrogen 7 program director Frank Ochmann is quick
to note that fuel-cell technology is a long way from production-ready, while
BMW’s approach could quickly be scaled up for the mass market.

That’s assuming you could get
hydrogen at the corner pump, of course. In reality, an H2 production and
distribution network is, at best, years away. That is why, said Ochmann, “For
now, the bi-fuel approach is needed.”

BMW researchers suggest
there’s a lot of room to keep improving the hydrogen-powered internal combustion
engine. A one-cylinder prototype, now being tested in the automaker’s Munich
labs, nearly triples the power output of the Hydrogen 7’s V-12, using techniques
like turbocharging and direct injection of liquid hydrogen.

BMW has often followed its own
approach to technology, and has earned a strong reputation and solid sales in
the process. Whether it will succeed with its hydrogen strategy remains to be
seen, but the Hydrogen 7 should provide a clear
indication.

750 is awesome

Overall Rating

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Performance

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Reliability

Aside from the fact that there are a still a few things I need to learn about this car, it is the best vehicle I've ever had. It's fun to drive - everything about it is as close to perfect as it can be.

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January 12, 2016

2013 BMW 7-Series 4-Door Sedan 740Li RWD

Business class at all times and performance car when needed

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I love what BMW accomplished in the 740 IL. A dose of luxury with the IL extension, and the basic 7 series amenities. Under the hood the 7 series delivers performance on a dime. The performance tubeless run...
I love what BMW accomplished in the 740 IL. A dose of luxury with the IL extension, and the basic 7 series amenities. Under the hood the 7 series delivers performance on a dime. The performance tubeless run flat tires are harsh and expensive while the self leveling suspension delivers a continuous smooth ride. The car is reliable and smart, shutting off power when you left unnecessary dome lights on overnight preventing the battery from draining and leaving you stranded. + More »

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April 17, 2015

For 2013 BMW 7-Series

Love my 750Li BMW!

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Car is amazing. Great fuel economy for this size automobile. Handles like a sports car, drives like a dream and performance with the twin turbos is outstanding.